354 MOSTLY MAMMALS 
Turning now to the interesting problem of coloration, 
the first feature that must strike the observer is that the 
pattern developed on the shells of most cowries is not 
seen by the animals themselves, for the reason that by 
the time the creature is fully protruded from its shell, 
the upper surface of the latter is more or less completely 
concealed by the fleshy lobes of the mantle. Accordingly, 
it would seem to be apparent that the colouring of these 
molluscs is developed for the purpose of protection, and 
not for the admiration of the different individuals or 
sexes of the same species. It might, indeed, be urged 
that as the lobes of the mantle are coloured similarly to 
the shell, or even more intensely, the colours are visible 
to the animals, and are therefore designed for mutual 
admiration. But had this been the object, it would surely 
have sufficed to restrict the coloration to the outer surface 
of the mantle-lobes, and not to have extended it on to 
their inner surfaces, from which it is deposited on the 
shell. As regards the utility of the cowry type of colora- 
tion for protective purposes, I have never had _ the 
opportunity of seeing the living molluscs in their native 
haunts, nor have I come across any description from those 
who have. Cowries, which are mostly tropical or sub- 
tropical molluscs, are, however, described as living in 
shallow water not far from the shore, and feeding on 
zoophytes; and so far as one can judge, their colours 
ought to harmonise well with the hues of the denizens of 
a coral-bank, or a mass of sea-anemones, many of which 
are more or less similarly spotted. If this explanation 
prove to be the true one, we can readily see why both the 
shells and the hard parts of cowries partake of the same 
striking types of coloration. 
Turning now to the consideration of the various types of 
